The ALICE experiment of the Large Hadron Collider, for the first time, directly measured the so-called “deadline,” which allowed physicists to accurately measure the size of the fundamental particles known as “charm quark.”
Many of the particles that make up the visible atmosphere around us are composite particles of tiny fundamental particles known as quarks. Protons and neutrons, for example, consist of three quarks each. There are six different quark “flavors” – top, bottom, top, bottom, unusual, and charm – each with different sizes, spins, and other quantum structures. Various combinations of quarks also form foreign particles. Quarks are held together by these composite particles by a powerful force, dispersed by a weightless particle called the gluon. Collectively, quarks and gluons are known as ‘partons.’
At the Large Hadron Collider (LHC) at CERN near Geneva, Switzerland, protons were propelled by a powerful magnetic field through a 16.8-kilometer (27-kilometer) tunnel to a power output of 6.8 TeV before crashing on its own. The collision produces a series of other particles, which release or decompose into other particles in the cascade that can illuminate the basic physics features.
In particular, quarks and gluons are produced and released in a cascade called Parton shower, where quarks release gluons, and gluons themselves can have other, less-energy gluons.
Scientists working on ALICE (short for A Large Ion Collider Experiment) are dragging a three-year proton-proton collision into evidence of a dead canon. In quantum chromodynamics, or QCD, which describes how strong forces work, the dead zone is a region where parts of a certain weight and energy are restricted from releasing gluons.
A drawing of the dead areas around the charm quark each time it releases gluon to the parton shower, preventing it from prolonged exposure to excess gluon.
Part of the difficulty is that the dead area can be filled with other subatomic particles created by proton-proton collisions. Tracking Parton’s movements through the shower as it constantly changes direction is also deceptive.
To solve this problem, scientists affiliated with ALICE developed a system in which they could reverse recordings of Parton showers in time, allowing them to evaluate where and when the shower products were released. In particular, they look for batteries that include charm quark. While making these showers, scientists discovered a region in the image of gluon radiation emitted during a parton shower when the release of gluons was suppressed. This is a dead console.
The findings are significant not only because they confirm the QCD prediction but also because they now offer a direct opportunity to accurately measure the weight of the charm quark, which is the belief and indirect estimates set at 1,275 +/- 25 MeV / c ^ 2. According to QCD, a dead cone is directly related to particle mass, and flawless particles cannot produce a quiet cone.
“Quarks are fundamental values in particle physics, but they cannot be reached and measured directly in experiments because, apart from high quarks, quarks are trapped within composite particles,” said Andrea Dainese, ALICE’s physic coordinator.
Therefore, discovering a dead cone could pave the way for a new era of quark physics.